Can you build an ADU in Phoenix, AZ?
The city's current ADU page says that on a lot with no more than one single-family detached primary dwelling, two ADUs are permitted in addition to the primary dwelling unit, and a third may be permitted under certain circumstances. Actual feasibility still depends on zoning district lot coverage, building code compliance, and site fit.
Confidence: medium · Last researched May 2026
Accessory Dwelling Unit (ADU) rules
Phoenix's current ADU page states that on a lot with no more than one single-family detached primary dwelling, two ADUs are permitted in addition to the primary dwelling unit, and a third ADU may be permitted under certain circumstances.
- Typical single-family zones are cited as examples, including R1-6 and R1-10
- Lot coverage rules from the zoning district still apply
- Each ADU may be up to 75% of the gross floor area of the main house
- ADU size may not exceed 1,000 sf for lots up to 10,000 sq. ft.
- ADU size may not exceed 3,000 sf for lots over 10,000 sq. ft.
- HOA rules should also be checked where applicable
Dimensional standards in Phoenix, AZ
| Required perimeter landscape setbacks in residential districts — maximum wall/fence height within required perimeter landscape setbacks | 40 inches — This appears in the Section 608 excerpt but the full context and applicability note were not fully captured in the source extract. |
Related questions
Are ADUs allowed in Phoenix, AZ?
Phoenix's current ADU page states that on a lot with no more than one single-family detached primary dwelling, two ADUs are permitted in addition to the primary dwelling unit, and a third ADU may be permitted under certain circumstances.
Full investor analysis
You've seen the general rule. The full Phoenix, AZ report shows which districts allow ADUs by-right vs. by special permit, the approval path and timeline, and the overlay/flood constraints that quietly kill ADU projects here. First town report is free.
Get the full Phoenix, AZ report free →More about Phoenix, AZ zoning
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This summary is AI-generated from public municipal sources and is not legal, engineering, or land-use advice. Always verify zoning with Phoenix, AZ officials before making decisions.
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